News / Science & Technology

    Astronomers Say Galaxy May Be Awash with Homeless Planets

    Artist's concept showing a free-floating planet with roughly the mass of Jupiter. These lone worlds, perhaps ejected from the planetary systems of their birth, are probably more common in our galaxy than stars.
    Artist's concept showing a free-floating planet with roughly the mass of Jupiter. These lone worlds, perhaps ejected from the planetary systems of their birth, are probably more common in our galaxy than stars.

    Astronomers say the Milky Way may be swarming with nomad planets wandering through space instead of orbiting a host star, and that the galaxy may have a greater number of unmoored planets than stars.

    Last year, astronomers detected about a dozen nomad planets wandering about the galaxy, using a technique called gravitational microlensing, in which the light of stars is momentarily refocused, and brightened, by the gravity of passing planets.

    At that time, scientists estimated there could be two Jupiter-sized nomad planets for every typical star with orbiting planets in the Milky Way.  Jupiter, a gas giant, is the largest planet in the solar system.

    A new analysis by researchers at the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University in California now estimates there could be 100,000 times more homeless planets than stars.

    Louis Strigari, a research scientist at Kavli, led the study that calculated the gravitational pull of the Milky Way galaxy and the amount of cosmic matter, or material, available to form nomad planets.

    "We imagined that the population of a dozen or so Jupiter-mass wandering or nomadic objects is just the tip of the iceberg relative to what’s really out there in terms of our galaxy," said Strigari.  "So, if one makes assumptions about how many there are below the mass below Jupiter, then one can obtain a bound [an estimate] on how many of these actually exist.

    While they might seem to be unlikely candidates for life as we know it, StrIgari says it is possible some of these wandering planets could harbor forms of bacterial life, even if they do not enjoy the heat of a sun.

    “If the object has a thick enough atmosphere and say there’s tectonic activity or radioactivity going on, on the surface of the planet, the heat could get trapped by the thick atmosphere and could potentially be hospitable to microbial life,” said the research scientist.

    Strigari also says there is a slight chance that two nomad planets could collide, flinging bacterial debris into other solar systems.

    Astronomers hope to confirm the number of wandering planets in the next decade, when a newer generation of larger, more powerful telescopes - including the space-based Wide-Field Infrared Survey Telescope and the ground-based Large Synoptic Survey Telescope proposed by the U.S. space agency (NASA) - begins operating.

    An article by Louis Strigari and colleagues on nomadic planets is published in the journal Monthly Notices of the Royal Astronomical Society.

    You May Like

    Top US General: Turkish Media Report ‘Absurd'

    General Dunford rejects ‘irresponsible' claims of coup involvement by former four-star Army General Campbell, who led NATO forces in Afghanistan before retiring earlier this year

    Video Saving Ethiopian Children Thought to Be Cursed

    'Omo Child' looks at efforts of one African man to stop killings of ‘mingi’ children

    Protests Over Western Troops Threaten Libyan 'Unity' Government

    Fears mount that Islamist foes of ‘unity' government plan to declare a revolutionaries' council in Tripoli

    This forum has been closed.
    Comments
         
    There are no comments in this forum. Be first and add one

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    London’s Financial Crown at Risk as Rivals Eye Brexit Opportunitiesi
    X
    VOA News
    July 25, 2016 5:09 PM
    By most measures, London rivals New York as the only true global financial center. But Britain’s vote to leave the European Union – so-called ‘Brexit’ – means the city could lose its right to sell services tariff-free across the bloc, risking its position as Europe’s financial headquarters. Already some banks have said they may shift operations to the mainland. Henry Ridgwell reports from London.
    Video

    Video London’s Financial Crown at Risk as Rivals Eye Brexit Opportunities

    By most measures, London rivals New York as the only true global financial center. But Britain’s vote to leave the European Union – so-called ‘Brexit’ – means the city could lose its right to sell services tariff-free across the bloc, risking its position as Europe’s financial headquarters. Already some banks have said they may shift operations to the mainland. Henry Ridgwell reports from London.
    Video

    Video Recycling Lifeline for Lebanon’s Last Glassblowers

    In a small Lebanese coastal town, one family is preserving a craft that stretches back millennia. The art of glass blowing was developed by Phoenicians in the region, and the Khalifehs say they are the only ones keeping the skill alive in Lebanon. But despite teaming up with an eco-entrepreneur and receiving an unexpected boost from the country’s recent trash crisis the future remains uncertain. John Owens reports from Sarafand.
    Video

    Video Migrants Continue to Risk Lives Crossing US Border from Mexico

    In his speech Thursday before the Republican National Convention, the party’s presidential candidate, Donald Trump, reiterated his proposal to build a wall along the U.S.-Mexico border if elected. Polls show a large percentage of Americans support better control of the nation's southwestern border, but as VOA’s Greg Flakus reports from the border town of Nogales in the Mexican state of Sonora, the situation faced by people trying to cross the border is already daunting.
    Video

    Video In State of Emergency, Turkey’s Erdogan Focuses on Spiritual Movement

    The state of emergency that Turkish President Recep Tayyip Erdogan has declared is giving him even more power to expand a purge that has seen an estimated 60,000 people either arrested or suspended from their jobs. VOA Europe correspondent Luis Ramirez reports from Istanbul.
    Video

    Video Calm the Waters: US Doubles Down Diplomatic Efforts in ASEAN Meetings

    The United States is redoubling diplomatic efforts and looking to upcoming regional meetings to calm the waters after an international tribunal invalidated the legal basis of Beijing's extensive claims in the South China Sea. VOA State Department correspondent Nike Ching has the story.
    Video

    Video Four Brother Goats Arrive in Brooklyn on a Mission

    While it's unusual to see farm animals in cities, it's become familiar for residents of Brooklyn, New York, to see a little herd of goats. Unlike gas-powered mowing equipment, goats remove invasive weeds quietly and without adding more pollution to the air. As Faiza Elmasry tells us, this is a pilot program and if it proves to be successful, the goat gardener program will be extended to other areas of New York. Faith Lapidus narrates.
    Video

    Video Scientists in Poland Race to Save Honeybees

    Honeybees are in danger worldwide. Causes of what's known as colony collapse disorder range from pesticides and loss of habitat to infections. But scientists in Poland say they are on track to finding a cure for one of the diseases. VOA’s George Putic reports.
    Video

    Video Wall Already Runs Along Parts of US-Mexico Border

    The Republican Party’s presidential nominee, Donald Trump, gained the support of many voters by saying he would build a wall to keep undocumented immigrants and drugs from coming across the border from Mexico. Critics have called his idea impractical and offensive to Mexico, while supporters say such a bold approach is needed to control the border. VOA’s Greg Flakus has more from the border town of Nogales, Arizona.
    Video

    Video New HIV Tests Emphasize Rapid Results

    As the global fight against AIDS intensifies, activists have placed increasing importance on getting people to know their HIV status. Some companies are developing new HIV testing methods designed to be quick, easy and accurate. Thuso Khumalo looks at the latest methods, presented at the International AIDS conference in Durban, South Africa.
    Video

    Video African Youth with HIV Urge More Support

    HIV, the virus that causes AIDS, is the top killer of teens in sub-Saharan Africa. But many youths say their experience with the virus is unique and needs to be addressed differently than the adult epidemic. VOA South African Correspondent Anita Powell reports.
    Video

    Video Pop-Up Art Comes to Your Living Room, Backyard and Elsewhere

    Around the world, independent artists and musicians wrestle with a common problem: where to exhibit or perform? Traditional spaces such as museums and galleries are reserved for bigger names, and renting a space is not feasible for many. Enter ArtsUp, which connects artists with venue owners. Whether it’s a living room, restaurant, office or even a boat, pop-up events are bringing music and art to unexpected places. Tina Trinh has more.
    Video

    Video Scotland’s Booming Whisky Industry Fears Brexit Hangover

    After Britain’s vote to leave the European Union, Scotland’s government wants to break away from the United Kingdom – fearing the nation’s exports are at risk. Among the biggest of these is whisky. Henry Ridgwell reports on a time of turmoil for those involved in the ancient art of distilling Scotland’s most famous product.

    Special Report

    Adrift The Invisible African Diaspora